<template>
  <div class="bottom-menu">
    <CheckButton
      id="check-button"
      class="select-all"
      :value="isSelectAll"
      @click.native="checkClick"
    ></CheckButton>
    <span @click="checkClick">全选</span>
    <span class="total-price">合计:¥{{totalPrice}}</span>
    <span class="buy-product" @click="buyClick">付款({{checkLength}})</span>
  </div>
</template>

<script>
import CheckButton from "./CheckButton";
import { mapGetters } from "vuex";

export default {
  name: "CartBottomBar",
  components: {
    CheckButton
  },
  data() {
    return {};
  },
  //监听属性 类似于data概念
  computed: {
    ...mapGetters(["cartList"]),
    // 合计
    totalPrice() {
      console.log('return this.cartList');
      
      return this.cartList
        .filter(item => {
          return item.checked;
        })
        .reduce((preValue, item) => {
          return preValue + item.price * item.count;
        }, 0)
        .toFixed(2);
    },
    // 付款
    checkLength() {
      return this.cartList.filter(item => item.checked).length;
    },
    // 全选按钮的状态
    isSelectAll() {
      if (this.cartList.length === 0) return false;
      return !this.cartList.find(item => !item.checked);
    }
  },
  //方法集合
  methods: {
    // 全选按钮
    checkClick() {
      if (this.isSelectAll) {
        this.cartList.forEach(item => {
          //全部选中的时候，变成全部不选中
          item.checked = false;
        });
      } else {
        this.cartList.forEach(item => {
          //只要一个没选中，变成全部选中
          item.checked = true;
        });
      }
    },
    // 付款按钮
    buyClick() {
      if (!this.isSelectAll) {
        this.$toast.show("请选择要购买的商品", 1500);
      }
    }
  }
};
</script>
<style scoped>
.bottom-menu {
  width: 100%;
  height: 44px;
  background-color: #eee;
  position: fixed;
  bottom: 49px;
  left: 0;
  box-shadow: 0 -2px 3px rgba(0, 0, 0, 0.2);
  font-size: 14px;
  color: #888;
  line-height: 44px;
  padding-left: 35px;
  box-sizing: border-box;
}

.bottom-menu .select-all {
  position: absolute;
  line-height: 0;
  left: 12px;
  top: 13px;
}

.bottom-menu .total-price {
  margin-left: 15px;
  font-size: 16px;
  color: #666;
}

.bottom-menu .buy-product {
  background-color: orangered;
  color: #fff;
  width: 100px;
  height: 44px;
  text-align: center;
  line-height: 44px;
  float: right;
}
</style>